1. Field
The inventive concept relates to an image processing method and apparatus, and more particularly to, an entropy encoding/decoding method and apparatus, which is applicable to a technique for hierarchical image processing, and a symbol encoding/decoding method and apparatus for the same.
2. Description of the Related Art
A digital image requires large-volume data processing. For large-volume data processing, most image processing techniques use various compression techniques for encoding/decoding an image in block units.
Generally, an image processing technique performs image processing in units of macro-blocks. Macro-blocks are each divided into a plurality of pixel blocks to be processed. Image coding is performed by image processing operations such as motion prediction, motion compensation, Discrete Cosine Transform (DCT), quantization, entropy coding, etc. Entropy coding is a coding scheme for improving image compression efficiency by using different-length codes. The codes indicate symbols according to the probabilities of occurrence of the symbols. That is, short code words are mapped to frequently-occurring symbols. To reduce the amount of processing of large-volume image data, some known techniques perform image encoding/decoding using a residual picture between images. Likewise, some known techniques process an image in various hierarchical structures using a residual image, such as is the case in an image codec of the VC series.